The purpose of this study was to evaluate whether dityrosine and advanced oxidation protein products (AOPP) reflect the severity of cisplatin-induced nephrotoxicity. Immunoexpression of dityrosine in kidneys and plasma AOPP concentration were examined up to day 4 post-cisplatin injection in rats. Cisplatin injection induced tubular injury on days 2-4 after injection and increased serum creatinine and BUN on days 3 and 4. On days 2-4, dityrosine was immunostained in the cytoplasm of damaged tubular cells, and their immunostaining intensity increased time-dependently. Plasma AOPP levels were significantly increased on days 3 and 4. These results suggest that expressions of dityrosine and AOPP were associated with the severity of renal injury and may be useful markers for the development of cisplatin-induced nephrotoxicity.